Malignant melanoma of the trunk: a retrospective review of 1128 patients.

Of 3,305 patients with malignant melanoma seen at the Park Medical Group, New York, during the period from 1935-1975, there were 1,128 (34%) melanomas of the trunk. There were 646 melanomas of the skin of the chest wall (20% of all melanomas) and 482 melanomas of the abdominal wall (15%). Of 646 patients treated more than ten years ago, 138 were indeterminate as they were seen only in consultation or with evidence of blood-borne disseminated melanoma. Of the determinate 516 patients, 148 are free of evidence of melanoma after ten years, giving an absolute ten-year survival rate of 29%. All patients who died or who were lost to followup were considered to have died from the melanoma. Of 386 patients with melanoma of the thoracic wall, 296 were determinate, of which 88 (30%) have survived the ten-year period. Of the 260 patients with melanoma of the abdominal wall, 220 were determinate and 60 (27%) are alive and well ten years post treatment. Of 340 males, 74 survived the ten-year period (22%), much lower than the 32% ten-year survival of the 148 females. A preceding mole which existed in 254 patients resulted in a ten-year survival rate of 45%, much higher than the 116 patients whose moles arose de novo, of which 27% survived the ten year period. Of fifty patients with superficial melanomas, 34 (68%) survived ten years. The ten-year survival of 386 patients with infiltrating melanomas was 22%. The ten-year survival for patients in Stage I was 59%. Of 262 patients in Stage II, the ten-year survival rate decreased to 14% and for the 60 patients in Stage III, the ten-year survival rate was 7%. The situation was the same for melanomas of the chest wall as well as for the abdominal wall. Elective node dissection was performed in 122 patients with Stage I melanoma and in 42 (34%), microscopic evidence of melanoma was observed. The ten-year survival of patients with positive nodes was 38%. In 62 patients, no elective node dissection was performed and in 26 (42%), clinical evidence of metastases developed later. Of these, six (23%) survived the ten year period after a therapeutic lymph node dissection. We conclude that melanomas over 1 ml in depth (Breslow's classification), or Levels III, IV and V in Clark-Mihm's classification, elective regional lymph node dissection is warranted. Further studies are necessary to determine the exact treatment procedures for the superficial (Level II) melanomas. Level I melanomas should not be included in a report of metastasizing malignant melanoma.